For troop protection, military surveillance missions often use autonomous vehicles, such as unmanned aerial vehicles (UAV's). The UAV flys a short low altitude flight, and uses an on-board camera system to acquire images, which it then delivers to a ground station.
A typical UAV camera system is a color system that is implemented with commercial off-the-shelf products. Some UAV's have a gimbaled pan/zoom/tilt (PZT) camera to acquire images. These cameras have a larger field of view (FOV) than fixed mount cameras, and thus decrease the amount of flight time required to observe a given area.
For small UAV's, the cameras are typically implemented with fixed mount systems, because size, weight, and power restrictions preclude the use of gimbaled systems. With a fixed mount camera, the FOV is smaller and the UAV must stay airborne longer to retrieve the same data as compared to a UAV with a gimbaled system.
Approved radio use for military datalinked imagery has driven small UAV video format to the analog National Television System Committee (NTSC) standard. This format limits the image on the ground station monitor to 640×480 pixels.
As a result of these constraints, present-day missions for small UAVs are limited to narrow, non-zoom field-of-view (FOV) images and ground area coverage. Longer flight times are required to complete reconnaissance, surveillance, and other mission objectives typically assigned to small UAVs.